I have a GlobalScape v3.31 to which I connect with SFTP and I have the same problem when files are >200KB or when the directory listed contains several files from 200 to ... depending on their name length and/or quantity inside the directory.
The issue first occured when WinSCP went from v4.0.7 to v4.1b. I think at that time the PuTTY code went to PuTTY 0.60.
I had the same issue with FileZilla when it went from v2.2.32 to v3.0.0.
When I use the psftp included in the PuTTY 0.60 package, all is fine.
Implementations MUST ignore excess data at the end of an otherwise
valid packet. Implementations MUST respond to unrecognized packet
types with an SSH_FX_OP_UNSUPPORTED error. This will allow the
protocol to be extended in a backwards compatible way as needed.
So it appears that the client is not following the spec. It should process the data up the lenght of the packet that it expects to receive.
Another section states:
The maximum size of a packet is in practice determined by the
client (the maximum size of read or write requests that it sends,
plus a few bytes of packet overhead). All servers SHOULD support
packets of at least 34000 bytes (where the packet size refers to
the full length, including the header above). This should allow
for reads and writes of at most 32768 bytes.
Granted the recommended approach is for the server to honor packet size stipulated by the client; however the spec is clear in that the client shouldn't simply error out if the packet exceeds the expected length." :shock:
Perhaps it can help?